Repeatable room temperature negative differential resistance in AlN/GaN resonant tunneling diodes grown on silicon

We report repeatable AlN/GaN resonant tunneling diodes (RTDs) grown on a silicon substrate by plasma-assisted molecular-beam epitaxy. The RTDs exhibit stable negative differential resistance without hysteresis at room temperature, where no degradation is observed even after 500 continuous bidirectional sweeps. The peak-to-valley current ratio is 1.36, and the peak current density is 24.38 kA/cm2. When the temperature is changed from 77 to 475 K, the peak current remains almost unchanged and the valley current increases gradually, resulting in a reduced peak-to-valley current ratio from 1.59 to 1.07. Our work softens the material quality constraints on realizing the room-temperature repeatable negative differential resistance and paves the way to low-cost III-nitride-based monolithic and hybrid microwave integrated circuits on large-size silicon wafers.